Method for manufacturing a receiver for refrigeration systems or the like



Nov. 20, 1962 J. KARMAZIN METHOD FOR MANUFACTURING RECEIVER FOR REFRIGERATION SYSTEMS OR THE LIKE Filed April 15. 1959 INVENTOR. JZ/ZW 477714;???

United States Patent 3,064,608 METHOD FOR MANUFACTURING A RECEIVER FGR REFRIGERATION SYSTEMS OR THE LIKE John Karmazin, Karmazin Products Corp., Wyandotte, Mich. Filed Apr. 15, 1959, Ser. No. 806,602 3 Claims. (Cl. 113120) It is an object of the present invention to provide a method for manufacturing fluid containers having tubular body portions made from rolled sheet material in which the body portion is of relatively large size compared to the thickness of the sheet material utilized.

It is a further object of the present invention to provide a method for manufacturing cylindrical wall fluid containers from rolled sheet material having bonded overlapped opposite lateral edges in which end closure members for sealing the ends of the container are utilized to maintain the size, shape and accurate positioning of the rolled sheet Wall during the bonding operation.

It is a still further object of the present invention to provide a method for manufacturing cylindrical Wall fluid containers from rolled sheet material having overlapped bonded marginal portions and fitted-with end closure members in which the bonded seam between the overlapped portions of the side wall and the fluid-tight I tion taken in conjunction with the accompanying drawings wherein:

FIGURE 1 is a side elevational view, partly in section, of a receiver for a refrigeration system embodying the principles of the present invention;

FIG. 2 is a sectional view of the structure illustrated in FIG. 1 taken along the line 22 thereof;

FIG. 3 is an'enlargcd fragmentary view of a portion of the structure illustrated in FIG. 2; and

FIG. 4 is a view similar to FIG. 3 illustrating another form of the invention.

While the invention is illustrated herein in the form of a receiver for use in a refrigeration system, the invention in its broader scope relates to sealed containers and particularly to containers made from sheet material and of relatively large diameter compared to the thickness of the sheet material used. The embodiment illustrated in FIG. 1 shows a receiver which constitutes a reservoir for the accumulation of the refrigerant in a refrigeration system. The receiver is generally in the form of a hollow cylinder and includes a cylindrical side wall 11 having a pair of end closure members or end covers 13 and 15 fitted over its opposite ends. Whileforming no part of the invention, the receiver is shown as being provided with an inlet fitting 17 and an outlet fitting 19 extending through an aperture 21 formed in the wall 11 and supporting an elongated bent tube 23 through which fluid is adapted to be drawn out of the'unit. The end closure members 13 and 15 are identical except that the cover 15 is shown as being fitted with a tube 25 filled with a lead plug 27 adapted to blow out under excessive heat and thereby prevent the explosion of the receiver. Each of the end covers 13 and 15 has a generally circular end wall portion 29 having a central circular portion 31 depressed inwardly to improve the resistance of the end cover to deformation under high internal pressure. Additionally, each end cover is formed with an annular flange 33 disposed coaxially with respect to the cylindrical side wall 11 and adapted to fit snugly over the opposite ends of the side wall 11. The inner surfaces 35 of the flanges 33 define cylindrical sockets which conformably engage the cylindrical outer periphery of the side wall 11 at the 3,064,008 Patented Nov. 20, 1962 opposite ends thereof. The end covers 13 and 15 may be inexpensively made from stamped sheet metal and the forming dies with which they are made serve to accurately establish the diameter of the flanges 33.

The cylindrical side wall 11 is formed from a rectangular sheet of sheet material such as sheet steel, which is rolled into cylindrical or tubular form. The opposite lateral margins 37 and 39 of the sheet are overlapped so that their faces 41 and 43, respectively, engage one another. In order to maintain the outer periphery 45 of the cylindrical wall 11 smoothly cylindrical, the marginal portion 37 is inwardly offset from the plane of the wall 11, thereby forming a shoulder 47 joining the face 41 of the marginal portion 37 with the outer periphery 45 of the wall 11. While the shoulder 47 may be of varying lengths depending upon its angle, it extends a radial distance equal to the thickness of the sheet material and may be positioned adjacent the free edge 49 of the opposite marginal portion 39. To bond the overlapping margins 37 and 39 together, one of the faces of said marginal portions is preferably provided with a groove such as the dovetail groove 51 shOWn in the face 43 of the marginal portion 39. The groove 51 is then filled with a bonding material 52 such as copper which will flow by capillary action between the faces 41 and 43 and between the shoulder 47 and edge 49 when the unit is placed in a brazing furnace.

A seal is formed between the outer periphery 45 of the cylindrical wall 11 and the inner cylindrical wall 35 of the end covers 13 and 15 by means of a bonding material such as brazing paste which is either placed on the outer periphery 45 of the wall 11 at the ends thereof or at the juncture of the edges of the flanges 33 and outer periphery 45, as indicated-at 65a and 65b in FIG. 1.

In the manufacture of the container of the present invention, the marginal portion 37 is preferably first grooved and the strip of bonding material 52 inserted and locked in the groove 51. This may be accomplished in a manner similar to that shown in my prior United States Patent No. 2,773,301. Thereafter, the marginal portion 37 is offset from the plane of the rest of the sheet from which the side wall 11 is formed. This sheet is then rolled in stages into the desired cylindrical form until the marginal portion 37 is brought into engagement with the opposite lateral margin 39. The sheet is then finally sized by being struck on an arbor. Thereafter, the end cover members 13 and 15 are fitted over the opposite ends of the wall 11 with a bonding material either between the annular flanges 33 and the outer periphery 45 of the wall 11 or adjacent the juncture of said parts. Should the diameter of the wall 11 be too great for the wall 11 to fit snugly within the cylindrical sockets of the end cover members 13 and 15, this condition may be corrected by greater overlapping of the margins 37 and 39 until the free edge 49 of the margin 39 abuts the shoulder 47. Thus, the correct fitting of all the elements is assured prior to the bonding operation. The entire assembly is then subjected to heat as by being passed through a brazing furnace, in order to set the bonding material. During the bonding operation the end covers 13 and 15 serve to maintain the cylindrical shape of the side wall 11 and prevent it from buckling or bending out of its desired dimension. Additionally, the end covers 13 and 15 serve to keep the abutting faces 41 and 43 of the overlapping portions 37 and 39, respectively, in engagement, thereby assuring the presence of sufficient capillary action to cause the bonding material to flow and producing a fluid-tight seam. While the offset marginal portion 39 interrupts the continuous cylindrical contour of the inner periphery of the side wall 11, this is of no particular consequence in the present invention. The bonding action occurs between the end covers 13 and 15 and the cylindrical side wall 11 at the outer 

